Pump with automatic return-to-zero pressure gauge

ABSTRACT

A pump includes a cylinder means, a handle and a hose. The cylinder means includes a base member, an outer cylinder, a linkage and an interior tube. A transverse air channel is disposed in the base member. A valve is installed in the outer cylinder and has a through-hole and a compartment disposed therein. The through-hole and the compartment respectively communicate with the transverse air channel. Air selectively passes through the transverse air channel via a non-return device that is provided in the compartment. A first end of the linkage is inserted into the outer cylinder and includes a piston installed thereto. The interior tube is inserted through the piston to the linkage and coupled to the valve of the outer cylinder. The handle is installed onto a second end of the linkage, and a pressure gauge is installed to the handle for measuring air pressure value in the linkage.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a pump having a pressure gauge provided on a handle thereof. In particular, the pressure gauge can return to zero automatically when the pump is not in use.

2. Description of the Related Art

A pressure gauge which is installed on a handle of a pump is easy for reading pressure values of the pressure gauge while inflating. However, after inflating, user needs to operate a relief valve of the pressure gauge manually for returning the pressure values of the pressure gauge to zero.

Referring to Taiwan Patent No. 408793, it discloses that a pressure gauge includes a shell 14, an indication panel 11, an indicator 201, a linkage 21, a cylinder 19, a spring 35, a relief valve 22 and a handle 13. The shell 14 is preferably transparent and provided over the top of the handle 13. The indicator 201 is slideably provided along graduations formed on the instrument 11 as the linkage 21 moves. The linkage 21 wound by the spring 35 is inserted into the interior of the cylinder 19. A piston 20 is attached to an end of the linkage 21. A button 23 is installed in the relief valve 22 for relieving pressure in an air channel 15 of the handle 13.

After inflating, users have to operate the pump manually for releasing the air in the pump so that the pressure gauge returns to zero. If users miss out this step, as operation of the pump once again, it will read a wrong pressure value.

The present invention will become clearer in light of the following detailed description of illustrative embodiment of this invention described in connection with the drawings.

SUMMARY OF THE INVENTION

Accordingly, the object is achieved by providing a pump that comprises a cylinder means including a base member, an outer cylinder installed onto the base member, a linkage having a first end and a second end, with the first end inserted into the outer cylinder, and an interior tube provided in the linkage; a transverse air channel disposed in the base member; a valve installed in the outer cylinder and including a through-hole that communicates with the transverse air channel; a piston provided at the first end of the linkage; wherein the interior tube is inserted into the linkage through the piston, and an end of the interior tube is fixed to the valve; a handle coupled to the second end of the linkage; and a pressure gauge installed to the handle for measuring an air pressure value in the linkage.

It is not necessary to further include a pressure-relief valve for releasing air from the linkage of the pump after inflating. However, the pressure gauge will return to zero automatically.

These and other aspects are addressed in relation to the Figures and related description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described via detailed illustration of the preferred embodiment referring to the drawings.

FIG. 1 is a perspective view of a pump with an automatic return-to-zero pressure gauge according to the first embodiment of the present invention.

FIG. 2 is a cross-section view of the pump shown in FIG. 1.

FIG. 3 is another cross-section view of the pump shown in FIG. 1, illustrating that the pump is used for inflating a tire.

FIG. 4 is another cross-section view of the pump shown in FIG. 1, illustrating air leaking from the pump.

FIG. 5 is a perspective view of a pump with an automatic return-to-zero pressure gauge according to the second embodiment of the present invention.

FIG. 6 is a cross-section view of the pump shown in FIG. 5.

FIG. 7 is a partial enlarged view in accordance with FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, a pump in accordance with a first embodiment in the present invention includes a cylinder means 10, a handle 20 and a hose 30. The pump in this case is preferably a foot pump. The cylinder means 10 includes a base member 11, an outer cylinder 12 installed onto the base member 11, a linkage 13 provided inside of the outer cylinder 12 and an interior tube 14 inserted through the linkage 13 and coupled to the outer cylinder 12. The handle 20 is installed to the linkage 13 opposite to the base member 11. The linkage 13 is coupled to the base member 11.

The base member 11 has two pedals 111 defined on two sides thereof and a transverse air channel 112 disposed therein transversely. First, second and third longitudinal channels 113, 114 and 115 are installed in the base member 11 longitudinally. The first, second and third longitudinal channels 113, 114 and 115 respectively communicate with the transverse air channel 112. Directions of the first, second and third longitudinal channels 113, 114 and 115 are respectively perpendicular to a direction of the transverse air channel 112. The first and second longitudinal channels 113 and 114 are provided in the center of the base member 11 and coupled to the outer cylinder 12. The third longitudinal channel 115 is provided adjacent the periphery of the base member 11 and coupled to the hose 30.

The outer cylinder 12 is mounted on the base member 11 and has a first end and a second end. A valve 121 is installed to the first end of the outer cylinder 12 against the base member 11. The valve 121 includes a through-hole 1211 and a compartment 1212 both longitudinally formed therein. The through-hole 1211 corresponds and communicates with the first longitudinal channel 113, and the compartment 1212 corresponds and communicates with the second longitudinal channel 114. A non-return device 122 is disposed in the compartment 1212 and includes a non-return valve 1221 and an elastic element 1222. The non-return valve 1221 is adapted for selectively sealing the compartment 1212 by the elastic element 1222. A cap 124 is installed to the second end of the outer cylinder 12. The linkage 13 extends from the outer cylinder 12 through the cap 124 and has a first end and a second end. The first end of the linkage 13 is inserted into the outer cylinder 12 and includes a piston 131. The second end of the linkage 13 is coupled to the handle 20. The interior tube 14 is inserted into the linkage 13 through the piston 131, and an end of the interior tube 14 is fixed to the valve 121.

The handle 20 is installed onto the second end of the linkage 13 and includes a pressure gauge 21. The pressure gauge 21 seals the second end of the linkage 13 and is able to measure a pressure value in the linkage 13.

The hose 30 has a first end and a second end. A connector valve 31 is provided at the first end of the hose 30 and coupled to the third longitudinal channel 115 of the base member 11 as to connect the hose 30 to the base member 11. A joint 32 is provided at the second end of the hose 30 and able to connect to a thing that is desired to be inflated.

Referring to FIGS. 3 and 4, it shows the pump is operated. The joint 32 of the hose 30 is connected to the thing that is desired to be inflated. In this case, the joint 32 of the hose 30 is connected to a valve of a bicycle tire as shown in FIG. 3. During inflating, user holds the handle 20 to drive the linkage 13 to reciprocatingly move with respect of the outer cylinder 12. Amount of air is inflated into the pump between the piston 131 of the linkage 13 and the outer cylinder 12. Therefore, the non-return valve 1221 disposed in the valve 12 is forced to press the elastic element 1222 by the air pressure. At first, the air in the outer cylinder 12 goes into the transverse air channel 112 of the base member 11 through the compartment 1212 and the second longitudinal channel 114. And then, after the air fulfills the whole transverse air channel 112, the air will go into the first and third longitudinal channels 113 and 115. The air, which passed through the first longitudinal channel 113, goes into the interior tube 14 and fulfills the interior of the linkage 13. So that the pressure gauge 21 installed onto the handle 20 can measure a pressure valve in the cylinder means 10.

After finishing inflation of the tire, the joint 32 of the hose 30 is removed from the valve of the tire. At the same time, the non-return valve 1221 seals the compartment 1212 by resilient press of the elastic element 1222. And then, the air in the linkage 13 and the interior tube 14 is released from the joint 32 through the transverse air channel 112 automatically. Therefore, the pressure gauge 21 of the pump can return to zero automatically, and it is not necessary to operate the pump additionally for releasing the air in the pump. Hence, it can also prevent from reading a wrong pressure valve on the pressure gauge as the pump is operated to inflate once again.

Referring to FIGS. 5 through 7, a pump in accordance with a second embodiment in the present invention includes a cylinder means 40, a handle 50 and a hose 60. The cylinder means 40 further includes a base member 41, an outer cylinder 42, a linkage 43 and an interior tube 44. The handle 50 is connected to the linkage 43, and the hose 60 is connected to the base member 41.

The base member 41 includes an air valve 411 transversely installed therein. A transverse air channel 4111 and a longitudinal air channel 4112 disposed in the air valve 411. A direction of the transverse air channel 4111 is perpendicular to a direction of the longitudinal air channel 4112. The transverse air channel 4111 communicates with the longitudinal air channel 4112.

The outer cylinder 42 has a first end a second end. The first end of the outer cylinder 42 is mounted onto the top of the base member 41. A valve 421 is disposed in the first end of the outer cylinder 42 against to the base member 41. The valve 421 includes a through-hole 4211 and a compartment 4212 both longitudinally formed therein. The through-hole 4211 corresponds and communicates with the longitudinal air channel 4112. A non-return device 422 is disposed in the compartment 4212 and includes a steel ball 4221 and an elastic element 4222. The steel ball 4221 is adapted for selectively sealing the compartment 4212 by the elastic element 4222. A cap 423 is installed to the second end of the outer cylinder 42. The linkage 43 extends from the outer cylinder 42 through the cap 423 and has a first end and a second end. The first end of the linkage 43 is inserted into the outer cylinder 42 and includes a piston 431. The second end of the linkage 43 is coupled to the handle 50. The interior tube 44 is inserted into the linkage 43 through the piston 431, and an end of the interior tube 44 is fixed to the valve 421 of the outer cylinder 42.

The handle 50 is installed onto the second end of the linkage 43 and includes a pressure gauge 51. The pressure gauge 51 seals the second end of the linkage 43 and is able to measure a pressure value in the linkage 43.

The hose 60 has a first end and a second end. A connector valve 61 is provided at the first end of the hose 60 and coupled to and communicating with the air valve 411 of the base member 41 as to connect the hose 60 to the base member 41. A joint 62 is provided at the second end of the hose 60 and able to connect to a thing that is desired to be inflated.

Before inflating, the joint 62 of the hose 60 is connected to the thing that is desired to be inflated. During inflating, to hold the handle 50 to drive the linkage 43 to reciprocatingly move with respect of the outer cylinder 42. Amount of air is inflated into the pump between the piston 431 of the linkage 43 and the outer cylinder 42. At first, the air in the outer cylinder 42 goes into the transverse air channel 4111 of the base member 41 through the compartment 4212 and the non-return device 422. And then, after the air fulfills the whole transverse air channel 4111 of the base member 41, the air goes into the interior tube 44 and fulfills the interior of the linkage 43. So that the pressure gauge 51 installed onto the handle 50 can measure a pressure valve in the cylinder means 40.

After finishing inflation, the joint 62 of the hose 60 is removed from the thing. At the same time, the steel ball 4221 of the non-return device 422 seals the compartment 4212 by resilient press of the elastic element 4222. And then, the air in the linkage 43 and the interior tube 44 is released from the joint 62 through the transverse air channel 4111 automatically. Therefore, the pressure gauge 61 of the pump can return to zero automatically, and it is not necessary to operate the pump additionally for releasing the air in the pump. Hence, it can also prevent from reading a wrong pressure valve on the pressure gauge as the pump is operated to inflate once again.

Thus since the invention disclosed herein may be embodied in other specific forms with out departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come with the meaning and range of equivalency of the claims are intended to be embraced therein. 

1. A pump comprising: a base member; an outer cylinder installed onto the base member; a linkage having a first end and a second end, with the first end of the linkage inserted into the outer cylinder; an interior tube provided in the linkage; a transverse air channel disposed in the base member; a through-hole that communicates the outer cylinder with the transverse air channel, with air passing through the through-hole from the outer cylinder into the transverse air channel and prevented from passing through the through-hole from the transverse air channel to the outer cylinder; a piston provided at the first end of the linkage; wherein the interior tube is inserted into the linkage through the piston, and wherein an end of the interior tube is fixed to the base member and communicates with the transverse air channel spaced from the through-hole; a handle coupled to the second end of the linkage; a pressure gauge installed to the handle and communicating with the linkage; and a hose having a first end and a second end, with the first end of the hose coupled to the base member in fluid communication with the transverse air channel; and with the second end of the hose coupled to a thing desired to be inflated; wherein air is pumped between the piston of the linkage and the outer cylinder during inflating; and the air in the outer cylinder goes into the transverse air channel of the base member through the through-hole as to fill the air in the transverse air channel, the interior tube and the interior of the linkage; wherein the pressure gauge measures an air pressure value in the linkage; wherein after finishing inflation, the hose is removed from the thing, and then, the air in the linkage and the interior tube is released from the hose through the transverse air channel automatically so that the pressure gauge of the pump can return to zero automatically.
 2. The pump as claimed in claim 1, further comprising a first longitudinal channel and a second longitudinal channel disposed in the base member, with the first and second longitudinal channels both in communication with the transverse air channel, with the interior tube in communication with the second longitudinal channel and with the through-hole communicating with the first longitudinal channel.
 3. The pump as claimed in claim 2, with the first and second longitudinal channels provided in the center of the base member.
 4. The pump as claimed in claim 3, further comprising a third longitudinal channel disposed in the base member away from the center of the base member, with the first end of the linkage communicating with the third longitudinal channel. 5-7. (canceled)
 8. The pump as claimed in claim 4, further comprising a connector disposed at the first end of the hose and a joint disposed at the second end of the hose, with the connector coupled to the third longitudinal channel for connecting the hose to the base member, and with the joint for connecting to thing desired to be inflated; wherein air is releasable from the joint after finishing inflation.
 9. The pump as claimed in claim 2, further comprising a compartment communicating with the second longitudinal channel and a non-return device installed in the compartment.
 10. The pump as claimed in claim 9, wherein the non-return device further includes a non-return valve and an elastic element, and with the non-return valve sealing the compartment via the elastic element.
 11. The pump as claimed in claim 1, further comprising an air valve transversely disposed in the base member, with the transverse air channel provided in the air valve, with a longitudinal air channel disposed in the air valve, and with the transverse air channel in communication with the longitudinal air channel, with the through-hole and the interior tube in communication with the longitudinal air channel.
 12. The pump as claimed in claim 11, further comprising a compartment and communicating with the longitudinal air channel and a non-return device installed in the compartment.
 13. The pump as claimed in claim 12, wherein the through-hole and the compartment respectively communicates with the longitudinal air channel of the air valve.
 14. The pump as claimed in claim 12, wherein the non-return device further includes a steel ball and an elastic element, and with the steel ball sealing the compartment via the elastic element. 15-18. (canceled)
 19. The pump as claimed in claim 12, further comprising a connector disposed at the first end of the hose and a joint disposed at the second end of the hose, with the connector coupled to the air valve of the base member, with the connector valve in communication with the air valve of the base member, and with the joint for connecting to thing desired to be inflated; wherein air is releasable from the joint after finishing inflation. 